Ruby on Rails：在html.erb中保留复选框状态

Question

How can I preserve the states of checkbox using session?

I tried the following but does not work.

   <form name="size">
  <input type="checkbox" name="size[]" value="1" <%@selected.include?("1")%> /> 1
  <input type="checkbox" name="size[]" value="2" <%@selected.include?("2")%> /> 2
  <input type="checkbox" name="size[]" value="3" <%@selected.include?("3")%> /> 3
  <input type="submit" value="Filter" /><br></form>

@selected is a instance variable in controller that stores the states of the checkbox using session.

Answer 1

Assuming @selected is an array, as I can infer from your code example, you can do

<input type="checkbox" name="size[]" value="1" <%= @selected.include?("1") ? "checked" : "" %> /> 1
<input type="checkbox" name="size[]" value="2" <%= @selected.include?("2") ? "checked" : "" %> /> 2
<input type="checkbox" name="size[]" value="3" <%= @selected.include?("3") ? "checked" : "" %> /> 3